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91.
Comparison of endothelial cell density estimated by contact and non-contact specular microscopy 总被引:2,自引:0,他引:2
PURPOSE: To compare a contact and a non-contact specular microscope in the determination of endothelial cell density. SUBJECTS AND METHODS: One hundred and twenty-one eyes from 70 patients who had undergone various degrees of photorefractive keratectomy for myopia were included. The endothelium was imaged by contact (Konan Clinical Specular Microscope) and non-contact (Topcon SP-1000) specular microscopy and the endothelial cell density estimated. RESULTS: The average endothelial cell density achieved by the contact specular microscope was 3011+/-298 cells/mm2 (mean+/-SD, n=121) and by the non-contact specular microscope 3015+/-265 cells/mm2 (n= 121). The difference in endothelial cell density between the contact and the non-contact specular microscope (contact minus non-contact) was -4+/-175 cells/mm2 (t=0.26, 2p>0.05 in a paired t-test). The sampling error on the estimated endothelial cell density was 76 cells/mm2 for the contact specular microscope and 74 cells/mm2 for the non-contact specular microscope. CONCLUSION: The average endothelial cell density and the precision of the measuring technique were similar for the contact and the non-contact specular microscope. Furthermore, the endothelial cell densities estimated by the two instruments at various values of anterior central corneal refractive power and central corneal thickness were similar. The two instruments can be used interchangeably. 相似文献
92.
Prolonged persistence on the ocular surface of fortified gentamicin ointment as compared to fortified gentamicin eye drops 总被引:1,自引:0,他引:1
PURPOSE: A comparative study on the elimination of gentamicin from the ocular surface and the concentration of gentamicin in the anterior chamber following application of either an ointment or eye drops containing equal concentrations (1.5%) of gentamicin. METHODS: A disc-diffusion test was used to determine the concentration of gentamicin in fornix inferior of 10 persons. The anterior chamber concentration of gentamicin was determined in 5 cataract patients by the TDX analyzer, Abbot Laboratories, II., USA. RESULTS: Ten minutes following application, the concentration of gentamicin was significantly higher in the eyes receiving ointment (310.6 mg/L) compared to drops (45 mg/L) (p<0.01). Furthermore, gentamicin could be detected 40 minutes after application in the eyes receiving ointment compared to 10 minutes in the eyes receiving drops. The anterior chamber concentration of gentamicin after application of either drops or ointment was lower than 0.6 mg/L and thus below detection limit. CONCLUSIONS: The persistence of gentamicin ointment was significantly longer on the ocular surface as compared to gentamicin eye drops. Gentamycin ointment may thus provide a means to reduce the high application frequency presently in use with eye drops to treat bacterial keratitis and thereby reduce patient inconvenience, especially during nighttime. 相似文献
93.
PURPOSE: To investigate the long-term effects and stability of refraction after radial keratotomy procedure. METHODS: Radial keratotomy was performed on 123 persons to reduce myopia (range: -1 to -13 diopters) in 1986 to 1989. A mean of 11.5 years later (range 10 to 13), 61 of these patients with 102 eyes underwent a standardised refractive examination where subjective spherical equivalent refraction was measured and compared to the preoperative and the one month postoperative refractive measurement collected from the patients records. RESULTS: There was a reduction in spherical equivalent from an average of -5.46 diopters (SD 2.38) preoperatively to -2.32 diopters (SD 1.96) 11.5 years postoperatively. The mean change in direction of myopia between 1 month and 11.5 years postoperatively was 0.17 diopters (SD 1.18). This change was not statistically significant. From 1 month to 11.5 years, 10 of the eyes had developed more than 1 diopter hyperopia, and 20% more than 1 diopter myopia. When asked directly, all patients were satisfied with the result of their operation in general; 2 patients still complained of glare. CONCLUSION: No significant changes in refraction were found between 1 month and 11.5 years after radial keratotomy. Previously reported long-term studies on this field have found a trend toward progressive hyperopia. No evidence of such change can be supported by this study. 相似文献
94.
RATIONALE: Several studies have provided indirect evidence that neuropeptide Y (NPY) may play a role in the regulation of ethanol consumption. However, the direct effects of central NPY administration on ethanol drinking are unclear. OBJECTIVE: This study examined the effects of NPY on ethanol, sucrose, and food consumption as well as its concomitant effects on the cortical EEG. METHODS: Wistar rats were implanted with cortical recording electrodes and a cannula in the third ventricle after using a sucrose substitution procedure to establish ethanol self-administration. NPY (0-15 microg/3.0 microl) was infused into the third ventricle prior to drinking sessions, when 10% ethanol (10E), 2% sucrose (2S), 0.5% sucrose (0.5S), or food were available. Behavior and cortical EEG were monitored during the sessions. RESULTS: NPY had no effect on the intake of 10E, 2S, or 0.5S, but NPY (15 microg/3.0 microl) significantly increased food intake. Under baseline drinking conditions, EEG power in the 6-8 Hz range was significantly greater when 2S was consumed compared to 10E. NPY decreased power in the 8-16 Hz range, decreased peak frequency in the 6-8 Hz range, and increased peak frequency in the 32-50 Hz range when 10E or 2S was available. CONCLUSIONS: These data suggest that NPY administration into the third ventricle preferentially regulates feeding compared to ethanol or sucrose drinking. In addition, since NPY significantly altered the cortical EEG in the absence of effects on ethanol and sucrose consumption, these data may indicate that NPY's cortical EEG effects are more related to its sedative or anxiolytic properties, rather than any effect on consumption. 相似文献
95.
Protective association of genetic variation in alcohol dehydrogenase with alcohol dependence in Native American Mission Indians 总被引:1,自引:0,他引:1
OBJECTIVE: Two alcohol dehydrogenase genes (ADH2 and ADH3 on chromosome 4) and one aldehyde dehydrogenase gene (ALDH2 on chromosome 12) exhibit functional polymorphisms. The goal of this study was to determine whether any associations exist between the ADH2, ADH3, and ALDH2 polymorphisms and alcohol dependence in a group of Native Americans. An additional goal was to determine if any associations exist between these polymorphisms and the endophenotype, maximum number of drinks ever consumed in a 24-hour period. METHOD: Mission Indian adults (N=340) were recruited for participation from reservations in southern California. Each participant completed an interview with the Semi-Structured Assessment for the Genetics of Alcoholism. A blood sample was collected from each participant for genotyping at the ALDH2, ADH2, and ADH3 loci. RESULTS: Sixty percent of all participants (72% of men and 53% of women) met lifetime DSM-III-R criteria for alcohol dependence. A significant difference in the ADH2 allele distributions was found between alcohol-dependent and non-alcohol-dependent participants. Those with alcohol dependence were significantly less likely to have the ADH2*3 allele (odds ratio=0.28) and significantly more likely to have the ADH2*1 allele (odds ratio=2.00) than those who were not alcohol dependent. Individuals with ADH2*3 reported a lower number of maximum drinks ever consumed in a 24-hour period, compared to those without this allele. CONCLUSIONS: These results are consistent with genetic linkage studies showing protective associations for alcohol dependence and related behavior on chromosome 4 and suggest that ADH2 polymorphisms may account for these findings. These results also highlight the utility of evaluating protective factors in populations with high rates of alcohol dependence. 相似文献
96.
The effect of remifentanil or fentanyl on postoperative vomiting and pain in children undergoing strabismus surgery 总被引:9,自引:0,他引:9
Eltzschig HK Schroeder TH Eissler BJ Felbinger TW Vonthein R Ehlers R Guggenberger H 《Anesthesia and analgesia》2002,94(5):1173-7, table of contents
Postoperative vomiting (POV) after strabismus surgery in children results in discomfort and prolonged hospital stays. Opioids increase the incidence of POV. Remifentanil has a context-sensitive half-life of 3 to 4 min, and how this short half-life influences POV in those patients is unknown. We conducted a prospective, double-blinded study in 81 ASA status I or II children from 2 to 12 yr of age undergoing elective strabismus surgery under general anesthesia. Patients were randomized to receive either remifentanil (bolus 1 microg/kg; infusion 0.1-0.2 microg x kg(-1) x min(-1)) or fentanyl (2 microg/kg, and 1 microg/kg every 45 min). POV episodes were recorded for 25 h. Pain scores were obtained by using an objective pain scale for 60 min during recovery. The number of patients who experienced POV did not differ significantly between groups (49% vs 48%). However, in the Remifentanil group, POV episodes were significantly less frequent (0.95 vs 2.2 episodes). In contrast, fentanyl was associated with lower pain scores during the first 30 min of recovery. We conclude that children undergoing strabismus surgery under balanced anesthesia with remifentanil, compared with fentanyl, showed less frequent POV. However, early postoperative analgesia was better with fentanyl. IMPLICATIONS: Opioids increase the incidence of postoperative vomiting (POV). Remifentanil is characterized by the shortest half-life of all opioids used in anesthetic practice. Therefore, we studied the effect of remifentanil on POV compared with the longer-acting opioid fentanyl in children undergoing strabismus surgery. 相似文献
97.
Deinstitutionalization (DI) of most of the chronic long-stay patients has taken place in the last decades in Germany. However, a "residual" group of patients often remains in psychiatric hospitals, with an ongoing controversy on an appropriate type of their care (community based vs. hospital). Clinical, functional and social characteristics of such schizophrenic patients still residing in the long-stay wards in the German state of Hesse after decades of DI are presented. The n = 266 patients investigated displayed a marked degree of negative symptoms and moderate positive symptoms but, however, severe social disabilities. In addition, the patients were very dependent in daily living, had an extremely impoverished social network and leisure activities. The findings contribute to the research on "difficult-to-place" patients described in the literature. 相似文献
98.
99.
Nurses' perceived barriers to the implementation of a Fall Prevention Clinical Practice Guideline in Singapore hospitals 总被引:1,自引:0,他引:1
Serena SL Koh Elizabeth Manias Alison M Hutchinson Susan Donath Linda Johnston 《BMC health services research》2008,8(1):105
Background
Theories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses' opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore. 相似文献100.